Integrating case-based with rule-based reasoning in body-in-white fixture design

Abstract

In this study, a case library for body-in-white (BIW) fixtures is constructed based on the structure of fixtures. The analytic hierarchy process (AHP) is applied to differentiate the factors influencing fixture cases. Weight calculations and the distribution of the weight coefficient of case properties are presented by adopting a 1-to-9 scaling algorithm. Furthermore, the similarity between cases is calculated using the nearest-neighbor approach. The parameterization of a fixture case is demonstrated in an example of a pneumatic fixture with two links. The rules for the revision of case parameters and the assembly positioning of case are given. A prototype case-based reasoning system for a fixture library is developed in C++ for NX software. Finally, a design case study is used to present the applicability and usability of the proposed reasoning system.